Tower Hamlets' mayor has denied allegations he is using council resources to politically campaign for Labour.
An A4 Labour Party leaflet for John Biggs, which was posted through letterboxes from the Isle of Dogs to Bow, carrys a town hall phone number and John Biggs' official email address.
Now the authority's legal monitoring officer is following up complaints about "facilities being used to promote a political party”.
However, Mr Biggs' party agent Graham Taylor said Labour "upholds principles of conduct in public life" and asked how can "giving out mayor Biggs’ contact details be an abuse of power?"
The council's monitoring officer sent a message on October 18 to remind recipients that "council resources, including email addresses and telephone numbers, are not to be used for campaigning or party political activity".
Canary Wharf independent councillor Andrew Wood said: "Labour is ignoring the legal officer’s instructions.
“They’re still distributing these leaflets weeks after being told it was wrong."
The mayor was contacted by the East London Advertiser, who acknowledged the leaflets were put out by Labour.
But Labour agent Mr Taylor defended using the mayor’s official contact data.
He told the paper: “Labour upholds principles of conduct in public life which include openness and accountability. How on earth can giving out mayor Biggs’ contact details be an abuse of power?
“We believe in letting residents get in touch so that John can help them.”
He distanced Labour from a previous administration, whose mayor had been banned from office by the courts in 2015 for election malpractice.
Graham insisted: “The current mayor would never use council resources for political campaigning.”
The council's monitoring officer is now looking at whether the leaflet breaches rules governing elections, it has been confirmed.
The authority said in a statement to the Advertiser: “The message to all members on October 18 was to remind them that council resources, including email addresses and telephone numbers, are not to be used for campaigning or party political activity.”
Complaints were made about the leaflet from households in Manchester Road, the nearby Chapel House Estate, Lanterns Court in Millharbour Road and from Bow Quarter housing complex in Fairfield Road.
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